ZX81 RAM Disk Operating System

[David G]

It is running on EightyOne v1.40:

EightyOne CONFIGURATION
1. On Options menu, select Hardware
2. On the "Advanced Settings" tab, click "RAM in 8K-16K Region"
3. Under "ROM File", choose "zx81.edition3.rom" (as normal)
NOTE: (It works with 50hz or 60hz)
4. Click OK

Then open ZXROS1.P. On the splash screen, press any key. NOTE: i couldn't get ZXROS2 to work

Yes, it is like MS-DOS, including being able to use options like DIR /W

Just curious if anyone on here actually knows what the RAM Disk OS is supposed to do

Dunno, but I gather the point of creating it is that a RAMDISK is used in the 8K slot. As long as you never turn the machine off (?)... the programs loaded will be loaded there for fast startup?

Code: Select all

TYPE SYSTNOTES.TXT

USE THE UTILITY "TI.EXE" TO LOAD ADDITIONAL PROGRAMS AND UTILITIES, GIVING THE FULL OS (SUPPLIED)"

[GCHarder]

The "Hunter" board used to have battery backup so it may have been useful for that.

[Moggy]

The "Hunter" board used to have battery backup so it may have been useful for that.

I have two of those C/W with the correspondence between Paul Hunter and the American customer he sold them to for his Gardening business and can confirm that it was indeed useful in that respect as you could store routines/programs for instant boot-up later, but now superseded by the ZXpand.

[bwinkel67]

I have two of those C/W with the correspondence between Paul Hunter and the American customer he sold them to for his Gardening business and can confirm that it was indeed useful in that respect as you could store routines/programs for instant boot-up later, but now superseded by the ZXpand.

Briefly looking at the Hunter board, it speaks of EPROM. Was that area between 8K and 16K writable by the ZX81? In other words, was the Hunber Board workable with the RAM Disk Operating System or did you need to write an EPROM with software and use that instead? If writable, that would be neat to try.

Could those be made open source since it looks like they were sold as kits, so all you really need is the circuit board and a parts list.

[1024MAK]

Hunter board - more information is available in this post or search the web with “TS1000 ZX81 Hunter board”.

Mark

[Moggy]

The board could be wired for EPROMs or static memory chips, I have both types.
If the board was populated with static memory chips you could write to the board, throw a switch to isolate the writing side of things which could corrupt the data if the switch was left open and the battery would keep the stored data live until either the battery ran out or you decided to change the contents. Whilst it couldn't write to an EPROM I did read an article somewhere which said it was possible to write to an EEPROM.

Battery life was said to be around ten years, in reality I never managed more than a year before the data was lost.




Another thread here which shows pictures of my own boards.

https://www.sinclairzxworld.com/viewtop ... ual#p48574

The manual can be found in this thread.

https://www.sinclairzxworld.com/viewtop ... &start=150

[David G]

Just curious if anyone on here actually knows what the RAM Disk OS is supposed to do

The "Hunter" board used to have battery backup so it may have been useful for that.

Bingo! I was just looking at stevemcd's notes in the ROSJUL98.zip archive. Steve wrote:

a DISK DRIVE ... allows storage during power-down

but

THE RAMDISK OPERATING SYSTEM uses RAM to emulate a DISK DRIVE and together with an 8K STATIC ram with battery, allows storage during power-down, much like a real disk - but with one huge advantage - S P E E D ! ! !

The O/S core is 100% optimised for performance and speed on a ZX81 - using the hardware to the full!

Back in the late 1990s this must have been wonderful. And still may be, if you have a STATIC ram board with battery backup. But now there are Zxpand and other speedy or somewhat-speedy storage solutions. The inventiveness of the ZX81 community has produced, and is continuing to produce, a surprising amount of solutions

[bwinkel67]

Back in the late 1990s this must have been wonderful. And still may be, if you have a STATIC ram board with battery backup. But now there are Zxpand and other speedy or somewhat-speedy storage solutions. The inventiveness of the ZX81 community has produced, and is continuing to produce, a surprising amount of solutions

Love seeing all the new hardware options for the ZX81, but also really love exploring the old hardware solutions people came up with when things were still sold as printed listing in the back of tech magazines. Just some creative solutions back then.